The aim of the proposed work is to analyze pancreatic secretions of patients suspected of having cancer of the pancreas or with a positive diagnosis of cancer of the pancreas and to compare them with secretory profiles obtained from healthy volunteers in the hope of detecting qualitative or quantitative abnormalities that might help in the early diagnosis of this disease. These studies will be accompanied by a similar investigation in hamsters during induction of pancreatic neoplasms with nitrosamines. Pancreatic tissue and fluid of groups of treated and untreated animals will be analyzed at regular intervals for changes in various parameters which in human patients have indicated the presence of pancreatic disease. Thus, ratios of trypsinogen variants, trypsin inhibitor, chymotrypsinogen and a number of lysosomal enzymes will be determined. Highly sensitive methods developed previously for investigation of human pancreatic fluid will be adapted for pancreatic tissue and fluid from hamsters. Data obtained from these assays will be correlated with concurrent histological studies in order to explore the possibility that changes in secretory proteins may precede recognizable histological abnormalities characteristic of tumor cells. Such changes or combination of changes might serve as sensitive markers for present or incipient pancreatic pathology.